The Gas Motions Within Granules on the Solar Surface Are

The gas motions within granules on the solar surface are

A) upward in the centers of some cells and downward in others; the gas cools as it passes between individual granules.
B) actually motionless. The dark regions are absorption features from gases in the photosphere.
C) upward in the bright cell centers and downward around the darker edges.
D) downward in the bright cell centers and upward around the darker edges.